<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>:has</title>
  <style>
    /* 目前浏览器不支持 */
    div:has(p) {
      color: red;
      border: 3px solid;
    }
  </style>
</head>
<body>
  <div class="has-p">
    <p>Hi</p>
  </div>
  <div class="has-a">
    <a href="#"></a>
  </div>
</body>
</html>